Infection control as a major World Health Organization priority for developing countries.

Healthcare-associated infection affects hundreds of millions of people worldwide and is a major global issue for patient safety. It complicates between 5 and 10% of admissions in acute care hospitals in industrialised countries. In developing countries, the risk is two to twenty times higher and the proportion of infected patients frequently exceeds 25%. A growing awareness of this problem prompted the World Health Organization to promote the creation of the World Alliance for Patient Safety. Prevention of healthcare-associated infection is the target of the Alliance First Global Patient Safety Challenge, 'Clean Care is Safer Care', launched in October 2005. After 2 years, a formal statement has been signed by 72 ministries of health as a pledge of their support to implement actions to reduce healthcare-associated infection; of these, 30 are developing countries. Additional countries, mostly from the developing world, have planned to sign by the end of 2008 and will represent in total more than three-quarters of the world's population. Given the emphasis of the proposed strategy on simple and affordable solutions, the impact of the Challenge is expected to be high in developing countries. The combined efforts expected under the Challenge have the potential to save millions of lives, prevent morbidities and long-term disability for hundreds of millions of patients, and lead to major cost savings through the improvement of basic infection control measures in any healthcare setting, regardless of resources available or level of development.

Effect of exercise training on heart rate variability in patients with new-onset left ventricular dysfunction after myocardial infarction.

BACKGROUND: Cardiac rehabilitation with exercise training alters sympathovagal control of heart rate variability (HRV) toward parasympathetic dominance in patients after acute myocardial infarction (MI). However, its effects on HRV in patients after MI with new-onset left ventricular dysfunction are yet unknown. We aimed to investigate the effects of 8 weeks of supervised, high-intensity exercise training on time- and frequency-domain measures of HRV in this selected patient population. METHODS AND RESULTS: Twenty-five men with an acute MI and a low ejection fraction were randomly assigned to enter or not to enter a training program in a regional rehabilitation center. HRV was evaluated before and after 1 and 2 months of training and at 12 months. Maximal exercise testing with respiratory gas exchange was performed at baseline and after training. Resting heart rate decreased (P <. 01) and the percentage of R-R intervals differing >50 ms from the preceding one (pNN50) increased (P <.05) after training. The standard deviation of R-R intervals (SDRR) tended to increase, but frequency-domain indexes remained unchanged. There was a significant decrease in SDRR (P <.05) and high-frequency power (P <.01) at 12 months in untrained patients. Exercise time increased by 38% and maximal oxygen uptake increased by 29% in the training group (P <. 01). CONCLUSIONS: Despite beneficial effects on clinical variables, exercise training did not markedly alter HRV indexes. A significant decrease in SDRR and high-frequency power in the control group suggests an ongoing process of sympathovagal imbalance in favor of sympathetic dominance in untrained patients after MI with new-onset left ventricular dysfunction.

[Reasonable and unreasonable hygiene measures in anesthesia in the intensive care unit]. / Sinnvolle und nicht sinnvolle Hygienemassnahmen in der Anästhesie und auf Intensivstationen.

The objective of this review is to describe which hygiene measures are appropriate and necessary in anaesthesia and the ICU and which are not, whereby unnecessary hygiene measures are those which are not substantiated by scientific data. The most effective single infection control measure is still hand disinfection between patient contacts. Unnecessary measures include routine sampling of environmental surfaces, disinfecting the floor in the ICU, protective gowns for visitors, so called in-line filters in the infusion system etc. Ventilator tubes only need to be exchanged once a week, even when no HMEs are used.

Methicillin-resistant Staphylococcus aureus in a teaching hospital: investigation of nosocomial transmission using a matched case-control study.

In early 1996 a hospital-wide methicillin-resistant Staphylococcus aureus (MRSA) epidemic was recognized in a 900-bed university hospital. In order to investigate hospital-specific transmission routes, a case-control study was carried out. Cases and controls were matched for age (+/- 10 years), sex, admission date (+/- 10 days) and clinical department on admission. Data on potential risk factors, were retrieved by chart review. Between June 1996 and February 1997, 67 patients with hospital-acquired MRSA were identified. Molecular typing showed that 85% of the cases carried an indistinguishable strain. The average time at risk for cases and controls was 17.3 and 23.7 days, respectively (P= 0.01). Seventeen patients (25.4%) developed infection. Conditional multivariate regression analysis showed that intensity of care (P= 0.002), number of transfers (P= 0.019), and fluoroquinolone therapy (P= 0.025) were independently associated with acquisition of MRSA. Intensity of care can be considered as a surrogate marker for a number of manipulations which represent the main risk factors for MRSA transmission. Frequent transfers within the hospital hinder, not only the epidemiological analyses, but also efforts to bring an outbreak under control. Our findings give epidemiological support to recent molecular studies which suggest that fluoroquinolone use may increase the transmissibility of MRSA in hospitals.

Influence of high-intensity exercise training on the ventilatory response to exercise in patients with reduced ventricular function.

BACKGROUND: Exercise training increases exercise capacity in patients with reduced ventricular function in part through improved skeletal muscle metabolism, but the effect training might have on abnormal ventilatory and gas exchange responses to exercise has not been clearly defined. METHODS: Twenty-five male patients with reduced ventricular function after a myocardial infarction were randomized to either a 2-month high-intensity residential exercise training program or to a control group. Before and after the study period, upright exercise testing was performed with measurements of ventilatory gas exchange, lactate, arterial blood gases, cardiac output, and pulmonary artery and wedge pressures. RESULTS: In the exercise group, peak VO2 and VO2 at the lactate threshold increased 29 and 39%, respectively, whereas no increases were observed among controls. Maximal cardiac output increased only in the exercise group (1.7 L x min(-1), P < 0.05), and no changes in rest or peak exercise pulmonary pressures were observed in either group. At baseline, modest inverse relationships were observed between pulmonary wedge pressure and peak VO2 both at rest (r = -0.56, P < 0.05) and peak exercise (r = -0.43, P < 0.05). Maximal VE/VCO2 was inversely related to maximal cardiac output (r = -0.72, P < 0.001). Training did not have a significant effect on these relationships. Training lowered VE/VO2, heart rate, and blood lactate levels at matched work rates throughout exercise and tended to lower maximal Vd/Vt. The slope of the relationship between VE and VCO2 was reduced after training in the exercise group (0.33 pre vs 0.27 post, P < 0.01), whereas control patients did not differ. CONCLUSIONS: Exercise training among patients with reduced left ventricular function results in a systematic improvement in the ventilatory response to exercise. Training increased maximal cardiac output, tended to lower Vd/Vt, and markedly improved the efficiency of ventilation. Peak VO2 and ventilatory responses to exercise were only modestly related to pulmonary vascular pressures, and training had no effect on the relationships between exercise capacity, ventilatory responses, and pulmonary pressures.

Influence of intensive physical training on urinary nitrate elimination and plasma endothelin-1 levels in patients with congestive heart failure.

BACKGROUND: Congestive heart failure (CHF) is associated with increased peripheral vascular resistance. Exercise-induced shear stress may release endothelial relaxing factors, such as nitric oxide (NO), and inhibit the production of vasoconstrictors such as endothelin-1 (ET-1) thereby modulating vascular tone. We examined the effect of intensive training on ET-1 plasma concentrations and NO-metabolite elimination in patients with CHF after acute myocardial infarction. METHODS: Seventeen patients with CHF after a myocardial infarction were randomized to an exercise group (n = 9), who performed physical training for 8 weeks, or a control group (n = 8) who received usual care. A physical examination, pulmonary function test, and a maximum exercise test were performed, and 24-hour urinary nitrate elimination and ET-1 in plasma were determined before and at the end of the study period. RESULTS: Maximal oxygen uptake remained unchanged in controls (17.9 +/- 1.4 to 18.1 +/- 1.5 mL/(kg min) but increased in the exercise group (from 20.4 +/- 0.75 to 26.7 +/- 1.4 mL/(kg min). After 8 weeks the urinary nitrate elimination in controls was significantly decreased (1.25 +/- 0.20 to 1.03 +/- 0.22 mmol/24 hours; P < 0.001), while it was unchanged in the exercise group (1.26 +/- 0.23 to 1.39 +/- 0.28; P = 0.71). Plasma ET-1 levels did not change after 8 weeks (7.87 +/- 0.62 versus 7.57 +/- 0.75 and 7.13 +/- 0.6 versus 7.35 +/- 0.7 pg/mL for control and exercise groups, respectively). CONCLUSION: In patients with CHF after acute myocardial infarction nitrate elimination decreases over the subsequent 2 months. This trend was reversed by training. Because nitrate elimination mirrors endogenous NO production, these results suggest that training may positively influence endothelial vasodilator function.

Effects of exercise training on limb blood flow in patients with reduced ventricular function.

BACKGROUND: Among the factors that contribute to limiting exercise tolerance in chronic heart failure are reduced peripheral blood flow and impaired vasodilatory capacity. Exercise training improves vasodilatory capacity in normal subjects, but controlled studies of exercise training evaluating upper and lower limb blood flow rates have not been performed in patients with reduced ventricular function. Improved vasodilatory capacity could help explain how training increases exercise capacity in these patients. METHODS: Twenty patients (mean age 55 +/- 6 years) with reduced left ventricular function (mean ejection fraction 32% +/- 6%) after a myocardial infarction were randomized to a 2-month high-intensity residential rehabilitation program or to a control group and were monitored over the subsequent year. Both groups were treated according to current practice with angiotensin-converting enzyme inhibition therapy. Training began 1 month after myocardial infarction. Baseline and postischemic flow rates were measured by plethysmography in both the upper and lower limbs 1 month, 3 months, and 1 year after the infarction. Peak oxygen uptake (VO2) and cardiac output were measured before and after training, and peak VO2 was determined again after 1 year. RESULTS: After 2 months of training peak VO2 increased 25%, VO2 at the lactate threshold increased 40%, and maximal cardiac output increased from 12.1 +/- 1.6 L/min to 13.9 +/- 2.4 L/min in the exercise group (all p < 0.05), whereas no differences were observed in the control group. At the 1-year follow-up no further increases in peak VO2 were noted in either group, but the higher value persisted in the trained group. However, changes in limb flow rates were poorly related to changes in both peak VO2 and maximal cardiac output. Improvements in baseline and postischemic flow rates occurred mainly in the lower limbs and were observed in the two groups to a similar degree. CONCLUSION: Exercise training is highly effective in improving exercise capacity in patients with reduced ventricular function after myocardial infarction. These improvements parallel an increase in maximal cardiac output, but they are unrelated to vasodilatory capacity. In patients with reduced ventricular function after myocardial infarction, lower limb vasodilatory capacity improves gradually over the subsequent year, and these improvements occur irrespective of exercise training.

A randomized comparison of exercise training in patients with normal vs reduced ventricular function.

BACKGROUND: Exercise training is recommended after myocardial infarction (MI) or bypass surgery in order to improve exercise tolerance. In some patients, the decrement in exercise capacity secondary to deconditioning and the left ventricular stunning associated with MI or coronary artery bypass graft (CABG) spontaneously improves after the event. However, the impact of the status of the left ventricle on these improvements is unknown. METHODS: Sixty-seven patients 1 month after MI or CABG were randomized to a training (n=34; age, 59+/-7 years) or a control group (n=33; age, 55+/-6 years). Forty-two patients had an ejection fraction >50% (22 in the training group and 20 in the control group), and 25 patients had an ejection fraction <40% (12 in the exercise group and 13 in the control group). After stabilization for approximately 1 month after the event, patients in the exercise group underwent 8 weeks of twice daily exercise at a residential rehabilitation center, while control patients received usual care. Initially and after 8 weeks, patients in both groups underwent maximal exercise testing with gas exchange and lactate analysis. RESULTS: Exercise training increased peak oxygen consumption (VO2) only in the reduced ejection fraction group (19.4+/-3.0 to 23.9+/-4.8 mL/kg/min; p<0.05); the exercise group with normal ventricular function did not change significantly. Changes in VO2 at the lactate threshold paralleled those of peak VO2 for both groups. Conversely, control patients with normal ventricular function increased peak VO2 spontaneously (20.8+/-3.9 to 24.8+/-3.5 mL/kg/min; p<0.01), whereas control patients with reduced ventricular function did not improve peak VO2. CONCLUSION: These data suggest that patients with depressed left ventricular function strongly benefit from rehabilitation, whereas most patients with preserved left ventricular function following MI or CABG tend to improve spontaneously 1 to 3 months after the event.

Influence of exercise training on blood viscosity in patients with coronary artery disease and impaired left ventricular function.

Exercise training has recently become an accepted therapeutic modality in chronic heart failure after myocardial infarction. Because the therapeutic mechanism behind it is controversial and not well understood, we analyzed the influence of exercise training on blood viscosity. Twenty-five patients with chronic heart failure (ejection fraction < 40%) after myocardial infarction were randomly assigned to either an 8-week intensive exercise program at a residential rehabilitation center or 8 weeks of sedentary life at home. Exercise consisted of two 1-hour walking sessions per day and four intensive bicycle ergometer training sessions of 40 minutes at 70% to 80% peak exercise capacity per week. Whole blood viscosity, viscosity at standardized hematocrit of 45% (P45) at high and low shear rates, and plasma viscosity were measured in a Couette-type viscometer before, during, and at the end of the study period. Exercise training, which significantly increased maximal cardiac output and oxygen uptake, did not change plasma viscosity, whole blood viscosity, and P45 significantly. Sedentary controls, however, had a higher whole blood viscosity and P45 after 8 weeks. No statistical difference was found, however, between the two groups. We conclude that blood rheology remains unaffected by exercise training in patients with chronic heart failure. The improvement of blood viscosity remains an interesting therapeutic option for the symptoms of these patients, which must be achieved by methods other than exercise training.

Effect of high intensity exercise training on central hemodynamic responses to exercise in men with reduced left ventricular function.

OBJECTIVES: The aim of this study was to evaluate the effects of high intensity exercise training on left ventricular function and hemodynamic responses to exercise in patients with reduced ventricular function. BACKGROUND: Results of studies on central hemodynamic adaptations to exercise training in patients with chronic heart failure have been contradictory, and some research has suggested that training causes further myocardial damage in these patients after a myocardial infarction. METHODS: Twenty-five men with left ventricular dysfunction after a myocardial infarction or coronary artery bypass graft surgery were randomized to an exercise training group (mean age +/- SD 56 +/- 5 years, mean ejection fraction [EF] 32 +/- 7%, n = 12) or a control group (mean age 55 +/- 7 years, mean EF 33 +/- 6%, n = 13). Patients in the exercise group performed 2 h of walking daily and four weekly sessions of high intensity monitored stationary cycling (40 min at 70% to 80% peak capacity) at a residential rehabilitation center for a period of 2 months. Ventilatory gas exchange and upright hemodynamic measurements (rest and peak exercise cardiac output; pulmonary artery, wedge and mean arterial pressures; and systemic vascular resistance) were performed before and after the study period. RESULTS: Maximal oxygen uptake (VO2max) increased by 23% after 1 month of training, and by an additional 6% after month 2. The increase in VO2max in the trained group paralleled an increase in maximal cardiac output (12.0 +/- 1.8 liters/min before training vs. 13.7 +/- 2.5 liters/min after training, p < 0.05), but maximal cardiac output did not change in the control group. Neither stroke volume nor hemodynamic pressures at rest or during exercise differed within or between groups. Rest left ventricular mass, volumes and EF determined by magnetic resonance imaging were unchanged in both groups. CONCLUSIONS: High intensity exercise training in patients with reduced left ventricular function results in substantial increases in VO2max by way of an increase in maximal cardiac output combined with a widening of maximal arteriovenous oxygen difference, but not changes in contractility. Training did not worsen hemodynamic status or cause further myocardial damage.

Effect of exercise training on myocardial remodeling in patients with reduced left ventricular function after myocardial infarction: application of magnetic resonance imaging.

BACKGROUND: There are conflicting reports on the effects of training on the remodeling process in post-myocardial infarction patients with ventricular damage. METHODS AND RESULTS: Twenty-five patients with reduced ventricular function (mean ejection fraction, 32.3+/-6%) after an anteroseptal or inferolateral myocardial infarction were randomized to an exercise group (n=12) or a control group (n=13). Patients in the exercise group resided in a rehabilitation center for 2 months and underwent a training program consisting of two 1-hour sessions of walking daily, along with four monitored 45-minute sessions of stationary cycling weekly. Before and after the study period, maximal exercise testing and cardiac MRI were performed. Oxygen uptake increased 26% at maximal exercise (19.7+/-3 to 23.9+/-5, P<.05) and 39% at the lactate threshold (P<.01) in the exercise group, whereas control values did not change. No differences were observed within or between groups in MRI measures of end-diastolic (187+/-47 pre versus 196+/-35 mL post in the exercise group and 179+/-52 pre versus 180+/-51 mL post in the control group), end-systolic volume (118+/-41 pre versus 121+/-33 mL post in the exercise group and 119+/-54 pre versus 116+/-56 mL post in the control group), or ejection fraction (38.0+/-9 pre versus 38.2+/-10% post in the exercise group and 37.0+/-10 pre versus 38.3+/-13% post in the control group). Myocardial wall thickness measurements at end diastole and end systole and their difference in 80 myocardial segments determined by MRI yielded no significant interactions between groups. When myocardial wall thickness measurements were classified by infarct or noninfarct areas, no differences were observed between groups over the study period. CONCLUSIONS: A high-intensity, 2-month residential cardiac rehabilitation program resulted in substantial increases in exercise capacity among patients with reduced left ventricular function. In contrast to some recent reports, the training program had no deleterious effects on left ventricular volume, function, or wall thickness regardless of infarct area.

Cisapride increases peak plasma and saliva ethanol levels under fasting conditions.

OBJECTIVES: Alcohol absorption is influenced by gastric first-pass metabolism through an alcohol dehydrogenase and the gastric emptying time. Whilst an influence of antisecretory drugs and aspirin on gastric alcohol metabolism has been described, the role of prokinetic drugs has not been determined. DESIGN: A randomized, placebo-controlled double-blind cross-over study was performed. SETTING: Out-patient facilities of a referral hospital. SUBJECTS: Eight male volunteers (age range 25-46 years). INTERVENTION: Treatment with two doses of either placebo or cisapride 150 micrograms/kg 7 h and 20 min before drinking 0.5 g/kg alcohol either in a fasting state or during a standardized meal (12 kcal/kg). MAIN OUTCOME MEASURES: Plasma and saliva ethanol concentrations were measured during 4 h. RESULTS: Cisapride increased peak plasma ethanol levels in fasting subjects from 15.6 (SD 1.4, 95%-KI 14.7;16.6) to 17.8 (SD 2.7, 95%-KI 15.9;19.7) mmol/L and saliva ethanol 30 min after alcohol ingestion from 11.4 (SD 2.2. 95%-KI 9.9;12.9) to 15.9 (SD 4.3, 95%-KI 12.9;18.8) mmol/L. A significant interaction between fasting state and drug intake was found for the 30 min saliva ethanol values (P < 0.05, ANOVA for repeated measurements). CONCLUSIONS: Cisapride may increase ethanol levels under fasting conditions. Patients treated with prokinetic drugs should be informed about this possibility.

Effect of residential cardiac rehabilitation following bypass surgery. Observations in Switzerland.

BACKGROUND: Cardiac rehabilitation in central Europe traditionally involves isolating patients in a residential idyllic setting where exercise is performed frequently but in a relatively unstructured fashion. Few studies have been performed on the effects of these programs among patients who have undergone bypass surgery. Recent data suggest that postbypass patients may enter these programs too soon after surgery or that exercise is not structured enough to distinguish the benefits of rehabilitation from those experienced by a control group. METHODS: Forty-two male patients (mean age, 58 +/- 7 years) were divided into exercise and control groups approximately 1 month after undergoing bypass surgery. Exercise training consisted of 1 h of group walking twice daily, with the intensity stratified into four levels based on initial exercise capacity. Using a crossover design, patients in the exercise group participated in rehabilitation for 1 month, followed by 1 month of usual care, while control patients underwent the opposite sequence. At 1, 2, and 3 months, patients in both groups underwent pulmonary function testing and maximal ramp exercise testing using lactate and gas exchange analysis. RESULTS: A main effect for maximal oxygen uptake was observed; significant improvements within each group occurred across each testing period (range, 5 to 13%; p < 0.05). However, there was no significant interaction between groups. Mean lactate levels throughout exercise were reduced within both groups (p < 0.01). A reduction in oxygen uptake for test 2 at the lactate threshold in the exercise group resulted in differences between groups in lactate, heart rate, and other gas exchange variables at this point. CONCLUSION: Similar changes occur in the functional status of postbypass surgery patients regardless of their participation in the short but concentrated programs common in central Europe. This suggests that a significant spontaneous effect of healing occurs in the recovery phase after surgery. These programs may have greater efficacy if they began later after surgery, lasted longer, or were more structured, and studies are needed to determine their effect on psychosocial factors and return to work.

[Fetomaternal transfusions in complicated and uncomplicated pregnancy]. / Fetomaternale Transfusionen bei kompliziertem und unkompliziertem Schwangerschaftsverlauf.

Fetomaternal bleeding in pregnancy is the most common cause of rhesus immunization. In this study we evaluated the amount of fetomaternal bleeding during pregnancies with and without complications. The data from 1204 patients are analyzed. Fetomaternal bleeding was of clinical relevance (HbF greater than 0.01%) in 6% of all uncomplicated pregnancies. There was no increased fetomaternal bleeding in pregnancies complicated by gestosis, preliminary labour, placenta praevia, trauma, and diabetes in pregnancy. In cases with premature rupture of the amnion or vaginal bleeding in pregnancy we observed an increased percentage of fetomaternal bleeding into the mother's circulation. Nearly 25% of all patients with hydrops fetalis had clinical relevant fetomaternal bleeding (HbF greater than 0.01%).